Motion Control & Kinematics Flashcards

In motion control, what does 'electronic gearing' allow?

Answer: Synchronizing multiple axes electronically to maintain a defined position ratio

Electronic gearing locks a follower axis to a master axis at a programmable ratio without a mechanical connection.

A trapezoidal velocity profile consists of which three phases?

Answer: Ramp-up, constant velocity, ramp-down

The trapezoidal profile accelerates at a constant rate, cruises at peak speed, then decelerates symmetrically.

What does 'backlash' refer to in a mechanical transmission?

Answer: The angular gap (lost motion) between mating gear teeth when direction reverses

Backlash is the dead-band in position that occurs when drive direction reverses due to clearance between gear teeth.

In multi-axis coordinated motion, what is 'contouring error'?

Answer: The difference between programmed and actual path of the end-effector

Contouring error measures how far the actual Cartesian path deviates from the commanded path during multi-axis motion.

Which mathematical representation is commonly used to express combined rotation and translation of a rigid body in 3D space?

Answer: 4×4 homogeneous transformation matrix

A 4×4 homogeneous matrix encodes a 3×3 rotation submatrix and a 3×1 translation vector in a single compact form.

What condition is described by the Nyquist stability criterion in a closed-loop motion control system?

Answer: The open-loop frequency response must not encircle −1+0j in the complex plane for stability

The Nyquist criterion states a closed-loop system is stable if the Nyquist plot of the open-loop transfer function does not encircle the critical point −1.

In kinematics, what distinguishes a 'prismatic' joint from a 'revolute' joint?

Answer: A prismatic joint allows linear sliding along an axis; a revolute joint allows rotation about an axis

Prismatic joints provide translational (sliding) motion along one axis, while revolute joints provide rotational motion about one axis.